Abstract
M.Sc. (Nanoscience)
The lack of easy access to clean water is an issue of great concern worldwide due to the fact that clean water is essential for life. Most water bodies are now contaminated with toxic organic pollutants, particularly textile dyes, as a result of the continuous discharge of industrial and agricultural wastewater into them. The presence of these contaminants in the water bodies pose serious threat to human health and aquatic life. The need for the appropriate technology for the removal of these pollutants from water has therefore become a subject of great interest in the scientific community.
Semiconductors have been widely used as the photocatalytic degradation of organic dyes in wastewater. However, this process encounters certain challenges. These challenges include the fast recombination rate of the photogenerated electron-hole pairs and the inability of the photocatalysts to function under visible light due to their wide band energy gaps. Steps to synthesize semiconductors that are able to utilize visible light and reduce the recombination rate of the electrons and holes are under consideration. In this study, we strive to synthesize semiconductors for the photocatalytic degradation of dyes and further improve their photocatalytic performance by doping them with metals and non-metals to form nanomaterials with different morphologies by use of surfactants.
Hydrothermal method of synthesis was adopted in the fabrication of the nanomaterials in this research work. All the synthesized catalysts were characterized by using X–ray powder diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, transmission electron microscopy (TEM), scanning electron microscopy (SEM), ultraviolet–visible (UV–Vis) spectroscopy, and energy dispersive spectroscopy (EDS). These techniques helped to obtain information on the nanomaterial’s structure, formation, morphology, size and elemental analysis.
Firstly, a comparison study on the effect of surfactant on the photocatalytic degradation performance of SnO nanoparticle was performed on the methyl orange dye under visible light illumination with interesting results. These samples were also observed to be present in the tetragonal romarchite phase of SnO. The band gaps of the surfactant modified SnO samples were wider and their visible light activities poorer compared to the pure SnO...